CN101487630B - Heat-exchange intensification apparatus and method for indirect medium heating furnace - Google Patents

Abstract

The invention relates to a heat exchange strengthening device and method for an indirect medium heating furnace. The unit consists of gas decoupling chamber, air decoupling chamber, starting purge blower, thermoacoustic coupled pulsation burner, pressure or vacuum gauge, non-condensable gas exhaust, rigid connections, coils, pot shell and smoke extraction Tube. Among them, the thermoacoustic coupled pulsation burner is composed of an air check valve, a gas check valve, a gas nozzle, a combustion chamber, a tailpipe and an exhaust decoupling chamber. The method is: the combustion chamber and the smoke pipe adopt the heat exchange method of air flow pulsation, eliminate the smoke flow boundary layer in the chamber wall and the smoke pipe wall, improve the convective heat transfer coefficient on the smoke side, and reduce the heat transfer area; The heat exchange between the heat medium (water) and the heated fluid coil forms a stable bead-like condensation heat transfer method through the mechanical vibration of the coil, which improves the convective heat transfer coefficient between the indirect heat transfer medium (water) and the heated fluid coil , reducing the heat transfer area.

Description

Heat exchange enhancement device and method for indirect medium heating furnace

(1) Technical field

The invention relates to a device and method for enhancing heat exchange of an indirect medium heating furnace, which is mainly used in oil field gathering and transportation projects, and can also be used in the field of boilers and other civil heating devices.

(2) Background technology

Oilfield crude oil and natural gas are mostly transported using water jacket furnaces. The characteristics of water jacket furnaces are that the indirect heat transfer medium-water is first heated by combustion and heat release, and then the water transfers the heat to the heated fluid immersed in water. The advantage of this is Avoid the danger of explosion caused by overtemperature and overpressure of the fluid caused by direct flame heating of the fluid, and smoke corrosion. Water jacket furnace is a type of furnace that adopts indirect medium heating. Its main heat exchange elements are combustion chamber, smoke pipe, and heated fluid coil. These heat exchange elements are all immersed in water and exchange heat through water. The specific heat exchange The process is as follows: fuel combustion transfers heat to the inner wall of the combustion chamber and the smoke pipe through convection and radiation, the process of heat transfer from the inner wall of the combustion chamber and the smoke pipe to the outer wall is heat conduction, and the heat is transferred to the outer wall of the combustion chamber and the smoke pipe through convection and radiation. The heat transfer medium (water) is the first link of heat transfer; the second link of heat transfer is that the heat transfer medium (water) transfers heat to the outer wall of the heated fluid coil through natural convection heat exchange, and the heat is transferred by the coil The process of transferring heat from the outer wall of the tube to the inner wall is heat conduction, and the inner wall of the coil transfers heat to the heated fluid through forced convection to complete the entire heat transfer process.

The above indirect medium heat transfer process has two heat transfer stages that directly affect the overall heat transfer efficiency, which in turn affects the size of the heat transfer area.

The first heat transfer link is the convective heat transfer on the side of the flue gas in the combustion chamber and the flue pipe. Because there is a heat-adhered surface layer between the flue gas and the inner wall of the pipe, the convective heat transfer coefficient on the flue gas side is very small. All the heat is transferred to the heat transfer medium (water), which will inevitably increase the heat exchange area, that is, increase the number of combustion chambers and smoke pipes. Even if measures such as increasing the flue gas flow rate are adopted, the increase in the convective heat transfer coefficient is quite limited. In addition, to increase the flue gas flow rate, forced air blast and induced air must be used, resulting in complex heating furnace system, extra power consumption, and high failure rate.

The second heat transfer link is the convective heat exchange between the heat transfer medium (water) and the outer wall of the heated fluid coil. Since the heat transfer medium (water) in the furnace only produces natural convection due to the density difference during heating, its convection The heat transfer coefficient is very low, much smaller than the forced convection heat transfer coefficient of the heated fluid in the coil. In order to transfer all the heat of the heat transfer medium (water) to the heated fluid, a sufficient heat transfer area is required, that is, a sufficient coil length.

To solve the problem of heat transfer in this link, phase-change heat transfer technology is widely used, but these phase-change heat transfer methods and technical means belong to the range of film condensation heat transfer. The latent heat of vaporization released at the time can only exchange heat with the outer wall of the coil through the liquid film layer, and the film layer becomes the main thermal resistance of condensation heat transfer. Only by destroying the liquid film layer to form bead-like condensation and making the steam directly contact with the coil wall can the heat transfer coefficient be improved.

From the above analysis, it can be seen that if the convective heat transfer coefficient of the above two heat transfer stages is increased, the number of combustion chambers, smoke pipes, and coils can be greatly reduced, the volume of the heating furnace can be reduced, and the steel consumption of the heating furnace can be reduced. . The present invention is a new method invented aiming at the above two heat transfer stages, which reduces the volume of the heating furnace and reduces the steel consumption.

(3) Contents of the invention

The object of the present invention is to provide a device and method for enhancing heat exchange of an indirect medium heating furnace.

The invention is an indirect medium heating furnace heat exchange strengthening device, and its technical scheme is: a gas decoupling chamber, an air decoupling chamber, a start-up purge fan, a thermoacoustic coupling pulsating burner, a pressure gauge or a vacuum gauge, and a non-condensable gas Exhaust device, rigid connector, coil, pot shell and exhaust pipe. Wherein, the thermoacoustic coupling pulsation burner and the coil are installed in the pot shell, and the thermoacoustic coupling pulsation burner and the coil are connected in the pot shell through a rigid connector; an air decoupling chamber is installed at one end of the pot shell, Start the purge fan to communicate with the air decoupling chamber and fix it on the pot shell. The gas decoupling chamber is installed in the air decoupling chamber; the other end of the pot shell is installed with a smoke exhaust pipe, which communicates with the thermoacoustic coupling pulse burner; the pressure gauge or The vacuum gauge and the non-condensable gas exhaust device are installed at the highest point of the pot shell and communicate with the pot shell.

A heat exchange enhancement device for an indirect medium heating furnace, characterized in that it is composed of a gas decoupling chamber, an air decoupling chamber, a starting purge fan, a thermoacoustic coupled pulsating burner, a pressure gauge or a vacuum gauge, and non-condensable gas exhaust device, rigid connectors, coils, pot shell and smoke exhaust pipe; the device adopts a split structure, which divides the pot shell into two independent cylinders, the upper and lower cylinders are connected by multiple thin tubes The thermoacoustic coupling pulsation burner installed in the lower cylinder is only used for steam generation, and the coil installed in the upper cylinder is only used for condensation heat exchange. The thermoacoustic coupling pulsation burner and the coil are connected by rigid connectors; the lower cylinder of the pot shell An air decoupling chamber is installed at one end, and the blowing fan is started to communicate with the air decoupling chamber and fixed on the lower cylinder of the pot shell. The gas decoupling chamber is installed in the air decoupling chamber; the other end of the lower cylinder of the pot shell is installed with a smoke exhaust pipe , communicated with the thermoacoustic coupling pulsation burner; the pressure gauge or vacuum gauge and the non-condensable gas exhaust device are installed at the highest point of the cylinder on the pot shell and communicated with the pot shell.

Wherein, the thermoacoustic coupling pulsation burner is composed of one or more air check valves, one or more gas check valves, one or more gas nozzles, a combustion chamber, one or more thinner tail The gas check valve is installed at one end of the combustion chamber and communicates with the combustion chamber; the gas nozzle is connected with the gas check valve in the combustion chamber; the air check valve is installed on the top of the combustion chamber and connected to the combustion chamber The other end of the combustion chamber is connected with one end of the tailpipe, and the two are connected; the other end of the tailpipe is connected with the exhaust decoupling chamber, and communicated with it.

Wherein, the tailpipe can be bent arbitrarily as required.

Among them, the thermoacoustic coupling pulsation burner is used to replace the traditional fire pipe and smoke pipe in the pot shell, and the thermoacoustic coupling pulsation burner is both a burner and a heat exchanger.

Wherein, a rigid connection is adopted between the thermoacoustic coupling pulsation burner and the heat exchange coil, and the rigid connection part is placed in the furnace shell.

Wherein, a non-condensable gas exhaust device is installed at the top of the heating furnace.

The invention relates to a method for enhancing heat exchange of an indirect medium heating furnace. The technical solution is to replace the combustion system, fire pipe and smoke pipe system of the existing water jacket furnace with a thermoacoustic coupling pulsation burner, and the thermoacoustic coupling combustion generates The pulsating airflow of a certain frequency destroys the heat-adhering surface layer in the combustion chamber, and increases the convective heat transfer coefficient on the flue gas side by nearly 10 times. The functions of the burner, fire pipe and smoke pipe of the heating furnace are integrated into one, which saves the fire pipe and smoke pipe of the traditional heating furnace. The thermoacoustic coupling pulsating burner is mainly composed of combustion chamber, air check valve, gas check valve, nozzle, tailpipe, decoupling chamber, exhaust pipe and other components. The internal acoustic characteristics of the burner itself are improved by pulsating supply of air and fuel. Coupled with the heat release characteristics of fuel combustion, a low-frequency longitudinal pulsating airflow inside the burner is formed, which destroys the boundary layer between the gas and the inner wall of the burner, and strengthens the convective heat transfer on the gas side.

The invention relates to a method for enhancing heat exchange of an indirect medium heating furnace. The technical solution is to immerse the thermoacoustic coupling pulsation burner below the liquid surface of the indirect medium in the drum, and the coil is located above the liquid surface, and through negative pressure or pressure The technical method of phase change enables condensation phase change heat to be generated between the heated medium steam and the outer wall of the coil. In order to avoid the formation of condensed liquid film on the outer wall of the coil during the phase transformation heat process, the thermoacoustic coupling pulsating burner will cause its own mechanical vibration when generating pulsating airflow, and the pulsating burner and the coil will be connected The coil is connected by a rigid structure, causing the coil to generate slight mechanical vibrations, causing the liquid film on the outer wall of the coil to not exist stably, changing the film-like condensation heat transfer to bead-like condensation heat transfer, and improving the convective heat transfer coefficient. Practice has shown that the bead-like condensation heat transfer The thermal coefficient can reach more than 5-10 times that of film condensation. Reduce the number and length of coils, reduce the volume of the heating furnace, and reduce the steel consumption of the heating furnace.

Among them, the thermoacoustic coupling pulsation combustion method is adopted, and the self-excited pulsation generated by the flue gas flow in the burner improves the convective heat transfer coefficient of the flue gas side.

Among them, the mechanical vibration generated by the thermoacoustic coupling pulsating burner itself is transmitted to the coil, causing the coil to generate tiny mechanical vibration.

Among them, the furnace is not filled with water, only part of the water is filled, and a heat exchange coil is installed in the upper space without water. The water is heated and boiled to generate steam. The working fluid flowing in the tube heat exchanger; the condensed water continues to be heated and vaporized, and this cycle goes on and on to realize condensation heat exchange.

The invention relates to a method and device for intensifying heat exchange of an indirect medium heating furnace, which has the following beneficial effects: thermoacoustic coupling pulsation combustion has the advantages of high combustion efficiency and low pollutant discharge, so the invention is used to replace the traditional oil field heating furnace, such as Phase change heating furnaces, water jacket furnaces, micro positive pressure furnaces, etc. can greatly improve thermal efficiency, greatly reduce pollutant emissions, and have obvious energy saving and low pollution effects. The burner, fire tube, and smoke tube are integrated into one part, the number and length of the coil are greatly reduced, and the structure of the heat exchange elements adopts a standard design, without any secondary processing, and without adding fins and other technical means to enhance heat exchange. , does not need any other auxiliary equipment (such as blower, induced draft fan, etc.) and chimney, the volume of the heating furnace is greatly reduced, the amount of steel consumption per unit power is also greatly reduced, and the manufacturing cost is greatly reduced. In addition, the invention is easy to realize full-automatic control, and the operation is safe and reliable.

(4) Description of drawings

Figure 1: Example of heating furnace (1).

Fig. 2: A-A sectional view of heating furnace embodiment (1).

Figure 3: Schematic diagram of the structure of a thermoacoustic coupled pulsation burner.

Figure 4: Example of heating furnace (2).

Fig. 5: B-B sectional view of heating furnace embodiment (2).

The symbols in the figure are explained as follows:

1. Gas decoupling chamber, 2. Air valve decoupling chamber, 3. Start purge fan, 4. Thermoacoustic coupling pulse burner, 5. Pressure gauge or vacuum gauge, 6. Non-condensable gas exhaust device, 7. Rigid connector, 8. Coil pipe , 9 pot shell, 10 exhaust pipe, 11 gas one-way valve, 12 air one-way valve, 13 gas nozzle, 14 combustion chamber, 15 tailpipe, 16 exhaust decoupling chamber, 17 upper and lower pot shell connecting pipes

(5) Specific implementation methods:

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Embodiment (1) of the present invention is the mechanical structure part of the water jacket furnace in the oil field as shown in Fig. 1 and Fig. 2. The heat exchange medium is water, which is used for heating crude oil or natural gas for export, and the fuel is natural gas. The heating furnace consists of a gas decoupling chamber 1, an air decoupling chamber 2, a start-up purge fan 3, a thermoacoustic coupling pulse burner 4, a pressure gauge or a vacuum gauge 5, a non-condensable gas exhaust device 6, a rigid connector 7, and a disc Pipe 8, pot shell 9 and exhaust pipe 10 are formed.

The connection relationship is as follows: the thermoacoustic coupling pulsation burner 4 and the coil 8 are installed in the pot shell 9 , and the thermoacoustic coupling pulsation burner 4 and the coil 8 are connected in the pot shell 9 through a rigid connector 7 . The air decoupling chamber 2 is installed at one end of the pot shell 9, and the blowing fan 3 is started to communicate with the air decoupling chamber 2, and is fixed on the pot shell (9), and the gas decoupling chamber 1 is installed in the air decoupling chamber 2; 9 The other end is equipped with a smoke exhaust pipe 10, which communicates with the thermoacoustic coupling pulse burner 4. A pressure gauge or a vacuum gauge 5 and a non-condensable gas exhaust device 6 are installed at the highest point of the pot shell 9 and communicate with the pot shell.

As shown in FIG. 3 , the thermoacoustic coupling pulsation burner 4 is composed of a gas check valve 11 , an air check valve 12 , a gas nozzle 13 , a combustion chamber 14 , a tailpipe 15 and an exhaust decoupling chamber 16 . The gas check valve is installed at one end of the combustion chamber and communicates with the combustion chamber; the gas nozzle is connected with the gas check valve in the combustion chamber; the air check valve is installed on the top of the combustion chamber and communicates with the combustion chamber; the other end of the combustion chamber is connected with the tail One end of the pipe is connected, and the two communicate; the other end of the tail pipe is connected to the exhaust decoupling chamber, and communicated with it.

The working process of the heating furnace embodiment (1) is as follows: the gas is sprayed into the combustion chamber 13 by the gas nozzle 11 through the gas check valve 11. After being ignited, the pressure of the combustion chamber 14 increases, causing the flue gas to pass through multiple tailpipes 15, exhaust The decoupling chamber 16 flows out, and at the same time, because the pressure of the combustion chamber 14 is higher than the pressure of the gas flow and the atmospheric pressure, the gas check valve 11 and the air check valve 12 are closed, and the supply of gas and air is stopped. The flow inertia of the combustion chamber causes the pressure in the combustion chamber to decrease, which is lower than the incoming gas pressure and atmospheric pressure, the gas check valve 11 and the air check valve 12 are opened, and the gas and air are re-supplied, and the gas and air are mixed and burned The high-temperature flue gas in the chamber 15 is ignited, and the previous working process is repeated. This process is repeated 20-100 times per second (frequency is 20-100Hz). Due to the periodic pulsation of the pressure in the combustion chamber 15, the flue gas flow is periodically Longitudinal pulsation flows out, scours the inner wall of the combustion chamber, tailpipe, and smoke exhaust pipe, destroys the smoke boundary layer on the inner wall, and improves the convective heat transfer coefficient on the side of the flue gas. At the same time, the pulsating burner 4 itself will also generate periodicity mechanical vibration. Since the pulsating burner 4 and the coil pipe 8 are connected by the rigid connection piece 7, the coil pipe 8 will also generate periodic micro mechanical vibrations.

The thermoacoustic coupled pulsating burner 4 transfers heat to the water in the pot shell 9, and the water is heated and evaporated to become water vapor to flow upward. When encountering the coil 8 flowing through crude oil or natural gas, the temperature of the outer wall of the coil is lower than that of the water vapor Due to the slight mechanical vibration of the coil 8, the outer wall of the coil 8 cannot form a liquid film formed by condensation of steam, so only bead-like condensation heat exchange can be produced, greatly The convective heat transfer coefficient on the outer wall side of the coil is greatly improved, and the bead-shaped condensation heat transfer transfers heat to the crude oil or natural gas in the coil 8, and the condensed water flows back to the liquid surface to continue to be heated and evaporated, so that the water evaporates and condenses reciprocally above the liquid surface. Complete the entire heat transfer process.

The selection of condensation heat transfer pressure conditions depends on the heating temperature requirements of crude oil or natural gas. When the heating temperature of crude oil or natural gas outlet is lower than 100 °C, the negative pressure condensation heat transfer method can be selected. The negative pressure condensation heat transfer boiler belongs to the normal pressure boiler. High safety and low manufacturing cost. The specific method is: close all valves on the pot shell 9, start the burner to heat, stop the delivery of crude oil or natural gas in the coil pipe, and when the pressure in the pot shell reaches a certain value, open the non-condensable gas exhaust device 6, and discharge the pot shell 9 When the air in the pot shell is exhausted and the pressure is close to the set value, close the non-condensable gas exhaust device 6, and then open the crude oil or natural gas in the coil, and the saturated steam in the pot shell will condense and cool down after being cooled, and the pot The temperature inside the shell is reduced to about 95°C. This process is equivalent to a constant volume exothermic cooling process. According to the thermophysical properties of water vapor, the pressure inside the shell will inevitably decrease, and the vacuum gauge 5 will maintain within the range.

When the heating temperature of the crude oil or natural gas outlet is higher than 100°C, the pressure condensation heat exchange method can be selected. The specific method is: close all valves on the pot shell 9, start the burner to heat, stop the delivery of crude oil or natural gas in the coil pipe, and when the pressure in the pot shell reaches a certain value, open the non-condensable gas exhaust device 6, and discharge the pot shell 9 When the air in the pot shell is exhausted and the pressure is close to the set value, close the non-condensable gas exhaust device 6, and then open the crude oil or natural gas in the coil, and the saturated steam in the pot shell will condense and cool down after being cooled, and the pot The temperature in the shell is reduced at about the set value, and the indication of the pressure gauge 5 is maintained within a certain range.

Embodiment of the present invention (two) as shown in Figure 3 and Figure 4, the heating furnace is composed of a gas decoupling chamber 1, an air decoupling chamber 2, a starting purge fan 3, a thermoacoustic coupling pulse burner 4, a pressure gauge or a vacuum Table 5, non-condensable gas exhaust device 6, rigid connector 7, coil 8, pot shell 9 and smoke exhaust pipe 10. The main difference from the heating furnace embodiment (1) is that the split structure is adopted, and the pot shell 9 is divided into two independent upper and lower cylinders, the upper and lower cylinders are connected by a plurality of thin tubes, and the lower cylinder is installed The thermoacoustic coupled pulsating burner 4 is only used for steam generation, and the coil 8 installed in the upper cylinder is only used for condensation heat exchange. The pulsating burner 4 and the coil (8) are connected by a rigid connector 7 .

The working process of the heating furnace embodiment (two) is as follows: the thermoacoustic coupling pulsation burner 4 transfers heat to the water in the lower cylinder of the pot shell 9, and the water is heated and evaporated into water vapor, which flows upward through the upper and lower pot shell connecting pipes 17. When the upper cylinder of the pot shell 9 encounters the coil 8 flowing through crude oil or natural gas, the temperature of the outer wall of the coil is lower than the temperature of the water vapor, and condensation heat exchange occurs between the water vapor and the coil 8. Due to the small mechanical vibration of the coil 8 , so that the outer wall of the coil 8 produces bead-like condensation heat exchange, and the heat is transferred to the crude oil or natural gas in the coil 8, reaching the design temperature for export. Condensed water flows back to the lower cylinder of the pot shell 9 through the upper and lower pot shell connecting pipes 17 to continue to be heated and evaporated, so that water evaporates and condenses back and forth between the upper and lower cylinders of the pot shell 9 to complete the entire heat transfer process.

In the embodiment (2) of the heating furnace, the lower cylinder of the pot shell 9 is a standard component that is only related to the power and has nothing to do with the physical properties of the user's working medium. Therefore, it is only necessary to design and manufacture a special pot according to the different needs of the user for the heating of the working medium. The shell 9 upper cylinder heat exchanger is assembled with the standard pot shell 9 lower cylinder, which can greatly reduce the design workload and shorten the manufacturing period. At the same time, because the two are separated, the volume of the two can be reduced, and it has the advantages of good pressure-bearing safe operation performance and convenient transportation.

The automatic control system and other requirements of the heating furnace can be carried out according to the process requirements of the heating furnace itself and the corresponding specification requirements, which will not be described in detail here.

Claims (10)

1. A heat exchange enhancement device for an indirect medium heating furnace, characterized in that: it is composed of a gas decoupling chamber, an air decoupling chamber, a start-up purge fan, a thermoacoustic coupled pulsating burner, a pressure gauge or a vacuum gauge, a non-condensable gas Exhaust device, rigid connector, coil pipe, pot shell and smoke exhaust pipe; wherein, the thermoacoustic coupling pulsation burner and coil pipe are installed in the pot shell, between the thermoacoustic coupling pulsation burner and the coil pipe It is connected in the pot shell through rigid connectors; an air decoupling chamber is installed at one end of the pot shell, and the blowing fan is started to communicate with the air decoupling chamber and fixed on the pot shell. The gas decoupling chamber is installed in the air decoupling chamber; the pot shell The other end is installed with a smoke exhaust pipe, which communicates with the thermoacoustic coupling pulsation burner; the pressure gauge or vacuum gauge and the non-condensable gas exhaust device are installed at the highest point of the pot shell and communicate with the pot shell. 2. An indirect medium heating furnace heat exchange enhancement device, characterized in that: it is composed of a gas decoupling chamber, an air decoupling chamber, a start-up purge fan, a thermoacoustic coupled pulsating burner, a pressure gauge or a vacuum gauge, a non-condensable gas Exhaust device, rigid connector, coil pipe, pot shell and smoke exhaust pipe; The thermoacoustic coupling pulsation burner installed in the lower cylinder is only used for generating steam, and the coil installed in the upper cylinder is only used for condensation heat exchange. The thermoacoustic coupling pulsation burner and the coil are connected by rigid connectors; An air decoupling chamber is installed at one end of the cylinder, and the blowing fan is connected to the air decoupling chamber and fixed on the lower cylinder of the pot shell. The gas decoupling chamber is installed in the air decoupling chamber; The smoke pipe communicates with the thermoacoustic coupling pulsation burner; the pressure gauge or vacuum gauge and the non-condensable gas exhaust device are installed at the highest point of the cylinder on the pot shell and communicate with the pot shell. 3. The heat exchange enhancement device for indirect medium heating furnaces according to claim 1 or 2, characterized in that: the thermoacoustic coupling pulsation burner is composed of one or more air check valves, one or more gas One-way valve, one or more gas nozzles, one combustion chamber, one or more thinner tailpipes and exhaust decoupling chamber; the gas one-way valve is installed at one end of the combustion chamber and communicates with the combustion chamber; the gas nozzle It is connected to the gas one-way valve in the combustion chamber; the air one-way valve is installed on the top of the combustion chamber and communicates with the combustion chamber; the other end of the combustion chamber is connected to one end of the tailpipe, and the two are connected; the other end of the tailpipe is connected to the exhaust decoupling chamber and communicate with it. 4. The heat exchange enhancing device for an indirect medium heating furnace according to claim 3, characterized in that the tailpipe can be bent arbitrarily as required. 5. A heat transfer enhancement method for an indirect medium heating furnace, characterized in that: the thermoacoustic coupling pulsation burner is submerged below the liquid surface of the indirect medium in the pot shell, the coil is located above the liquid surface, and through negative pressure or pressure phase change The technical method makes condensation phase change heat generated between the heated medium steam and the outer wall of the coil; in order to avoid the formation of a condensed liquid film on the outer wall of the coil during the phase change heat process, a thermoacoustic coupled pulsation burner is used to generate pulsation At the same time of the air flow, it will cause its own mechanical vibration characteristics. The thermoacoustic coupling pulsation burner and the coil are connected by a rigid structure, which will cause the coil to produce small mechanical vibrations, resulting in the liquid film on the outer wall of the coil cannot exist stably and become The film condensation heat transfer is bead condensation heat transfer, which improves the convective heat transfer coefficient. 6. The heat transfer enhancement method for an indirect medium heating furnace according to claim 5, characterized in that: the thermoacoustic coupling pulsation combustion method is adopted, and the self-excited pulsation generated by the flue gas flow in the burner improves the convective heat transfer coefficient of the flue gas side . 7. The method for enhancing heat exchange of an indirect medium heating furnace according to claim 5, characterized in that: the mechanical vibration generated by the thermoacoustic coupling pulsation burner itself is transmitted to the coil, causing the coil to generate micro mechanical vibration. 8. The heat transfer enhancement method for an indirect medium heating furnace according to claim 5, characterized in that: the furnace is not filled with water, only part of the water is filled, and a heat exchange coil is arranged in the upper space without water, and the water is heated and boiled to generate steam , the steam exchanges heat with the low-temperature coil wall, condenses into water, and transfers heat to the working medium flowing in the coil heat exchanger; the condensed water continues to be heated and vaporized, and this cycle goes on and on to realize condensation heat exchange. 9. The heat exchange enhancement device for indirect medium heating furnaces according to claim 1, 2 or 3, characterized in that: a thermoacoustic coupling pulsation burner is used to replace the traditional fire tube and smoke tube in the pot shell, and thermoacoustic coupling pulsation combustion The burner is both a burner and a heat exchanger. 10. The heat exchange enhancement device for indirect medium heating furnace according to claim 1, 2 or 3, characterized in that: the thermoacoustic coupling pulsation burner and the heat exchange coil are rigidly connected, and the rigid connection is placed Inside the pot shell.

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